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Tag Archives: ePassport

Currently in context of ePassports ICAO LDS 2.0 is a hot topic. Today I would like to tell you some interesting details about an interim version, called LDS 1.8. The Logical Data Structure (LDS) specifies the way to store and protect data on ePassports (eMRTDs). Especially in the context of ePassports, this specification is required for global interoperability. Current eMRTDs are using ICAO LDS 1.7 to organise and store the data. This post describes ICAO LDS 1.8, the difference to LDS 1.7 and the motivation to use this new data structure.

Summary of File Structure (Source: Doc 9303 Part 10)

The specification Doc 9303 Part 10 (‘Logical Data Structure (LDS) for Storage of Biometrics and Other Data in the Contactless Integrated Circuit (IC)’) describes all data groups and elementary files used in context of ePassports. The file EF.COM is a kind of directory where all data groups are listed. Additionally, there is a version number encoded that represents the version number of the local data structure and a Unicode Version that is used (typically 4.0.0).

So with the ‘directory’ of the ePassport, an inspection system should be able to read all relevant files of the chip. The procedure to read the information is explained in a previous posting. But addressing the files via EF.COM is risky because EF.COM cannot be trusted. EF.COM is not hashed and not signed and cannot be verified during Passive Authentication. This implies EF.COM can be manipulated easily and the manipulation in turn can be hidden easily. This way an attacker can downgrade a secure chip e.g. with Extended Access Control (EAC) to a simple chip with Basic Access Control (BAC) only by deleting the files in EF.COM. In other words, this way to detect a file on an ePassport is insecure and should be avoided.

By using the command SELECT FILE, one can also detect a file. With this command you can try to select a file in the file system of the chip and if the chip responds positively you might be sure that this file is available. This way involves the problem that some system integrators personalise the chip with empty data groups. So the chip responds positively to a SELECT FILE command, but the file does not really exist. To put it in a nutshell, this way is not sufficient either.

With ICAO LDS 1.8 all information stored in EF.COM has been duplicated now in file EF.SOD. This means that the EF.COM is deprecated and can be removed from the ePassport with the next LDS version after V1.8. By doing this a file can be detected by reading EF.SOD in a secure way. Without the file EF.COM the ePassport will be even more secure.

From a testing perspective a new logical data structure means some more tests. The ICAO test specification for ePassports is already prepared for the data structure, e.g. test suite LDS_D includes some tests for LDS 1.8, whereas the tests for inspection systems are currently missing.

Conclusion: With ICAO LDS 1.8 you can use a way to describe the content of your ePassport in a secure way. This way the insecure file EF.COM can be omitted in the future and the inspection procedure can use secure EF.SOD to get information about the stored data groups.

Update: You can find a discussion concerning LDS 1.8 on LinkedIn here.

There is an maintenance update of ICAO’s test specification ‘RF and Protocol Testing Part 3‘ available since today. The specification is focusing on conformity testing and protocol testing for ePassports implementing protocols like BAC and Supplemental Access Control (SAC) respective PACE v2.

The Technical Advisory Group (TAG) of ICAO endorsed the release on the ICAO website, so from now on the test specification can be referenced officially. In version 2.07 of the test specification there are no technical or fundamental changes, but editorial changes. The following test cases are modified in the new release 2.07:

ISO7816_B_16: Profile corrected

ISO7816_B_26: Added version

ISO7816_B_34: Profile corrected

ISO7816_B_52: Profile corrected

ISO7816_D_06: Updated version

ISO7816_D_09 – ISO7816_D_22: Profile corrected and version updated

ISO7816_E_09 – ISO7816_E_22: Profile corrected and version updated

ISO7816_F_20: Profile corrected and version updated

ISO7816_G_20: Profile corrected and version updated

ISO7816_O_12: Deleted obsolete Test-ID

ISO7816_O_13: Corrected sequence tags

ISO7816_O_31: Deleted obsolete Test-ID

ISO7816_O_35: Added missing caption

ISO7816_P_xx: Deleted sample in description of step 1 (‘i.e. more than one set of
domain parameters are available for PACE’)

International Civil Aviation Organization (ICAO) has released the seventh edition of ICAO Doc 9303. This document is the de-facto standard for machine readable travel documents (MRTD). It specifies passports and visas starting with the dimensions of the travel document and ending with the specification of protocols used by the chip integrated in travel documents.

A fundamental problem of the old sixth edition of Doc 9303 (released 2006) resides in the fact, that there are in sum 14 supplemental documents. All of these supplements include clarifications and corrections of Doc 9303, e.g. Supplement 14 contains 253 different issues. Additionally, there are separate documents specifying new protocols like Supplemental Access Control (SAC) also known as PACE v2. So ICAO started in 2011 to re-structure the specifications with the result that all these technical reports, guidelines and supplements are now consolidated in the seventh edition of ICAO Doc 9303. Also several inconsistencies of the documents are resolved. On this way several technical reports, like TR – Supplemental Access Control for MRTDs V1.1 and TR LDS and PKI Maintenance V2.0, are obsolete now with the seventh edition of Doc 9303.

The new edition of ICAO Doc 9303 consists now of twelve parts:

Part 1: Introduction

Part 2: Specifications for the security of the design, manufacture and issuance of MRTDs

Part 3: Specifications common to all MRTDs

Part 4: Specifications for Machine Readable Passports (MRPs) and other td3 size MRTDs

Part 9: Deployment of biometric identification and electronic storage of data in eMRTDs

Part 10: Logical Data Structure (LDS) for storage of biometrics and other data in the contactless integrated circuit (IC)

Part 11: Security mechanisms for MRTDs

Part 12: Public Key Infrastructure (PKI) for MRTDs

From a protocol point of view there are two interesting parts in Doc 9303: part 10 describes the data structures used in a smart card to store information. In addition part 11 describes the technical protocols to get access to this data, e.g. Chip Authentication Mapping.

Special thanks to Garleen Tomney-McGann working at ICAO headquarter in Montreal. As a member of the Traveller Identification Programme (TRIP) she has coordinated all the activities resulting in the seventh release of ICAO Doc 9303.

Supplemental Access Control (SAC) is a set of security protocols published by ICAO to protect personal data stored in electronic travel documents like ePassports and ID cards. One protocol of SAC is the well known Password Authenticated Connection Establishment (PACE) protocol, which supplements and enhances Basic Access Control (BAC). PACE was developed originally by the German Federal Office for Information Security (BSI) to provide a cryptographic protocol for the German ID card (Personalausweis).

Currently PACE supports three different kinds of mapping as part of the security protocol execution:

Generic Mapping (GM) based on a Diffie-Hellman Key Agreement,

Integrated Mapping (IM) based on a direct mapping of a field element to the cryptographic group,

Since Version 1.1 of ICAO technical report TR – Supplemental Access Control for MRTDs there is a specification of a third mapping procedure for PACE, the Chip Authentication Mapping (CAM), which extends established Generic Mapping. This third mapping protocol combines PACE and Chip Authentication into only one protocol PACE-CAM. On this way it is possible to perform Chip Authentication Mapping faster than both separate protocols.

The chip indicates the support of Chip Authentication Mapping by the presence of a corresponding PACEInfo structure in the file EF.CardAccess. The Object Identifier (OID) defines the cryptographic parameters that must be used during the mapping. CAM supports AES with key length of 128, 192 and 256. But in contrast to GM and IM there is no support of 3DES (for security reasons) and only support of ECDH.

The mapping phase of the CAM itself is 100% identical to the mapping phase of GM. The ephemeral public keys are encoded as elliptic curve points.

To perform PACE a chain of GENERAL AUTHENTICATE commands is used. For CAM there is a deviation in step 4 when Mutual Authentication is performed. In this step the terminal sends the authentication token of the terminal (tag 0x85) and expects the authentication token of the chip (tag 0x86). Additionally, in CAM the chip sends also encrypted chip authentication data with tag 0x8A to the terminal.

If GENERAL AUTHENTICATION procedure was performed successfully, the terminal must perform the following two steps to authenticate the chip:

Read and verify EF.CardSecurity,

Use the public key of EF.CardSecurity in combination with the mapping data and the encrypted chip authentication data received during CAM to authenticate the chip.

It is necessary to perform Passive Authentication in combination with Chip Authentication Mapping to consider that the chip is genuine.

The benefit of Chip Authentication Mapping is the combination of PACE and Chip Authentication. The combination of both protocols saves time and allows a faster performance than the execution of both protocol separately.

You can find interesting information concerning CAM in the patent of Dr. Dennis Kügler and Dr. Jens Bender in the corresponding document of the German Patent and Trademark Office.

Currently you can find the well-known test tool Titan under the patronage of the Eclipse Foundation (proposal). This tool was developed by Ericsson several years ago to the test internet protocol (IP). Titan bases on TTCN-3, a test language focusing on communication protocols. This keeps me in mind an old project with ETSI where we used TTCN-3 to test ePassport readers concerning BSI TR-3105 part 5.1.

From end of 2009 to middle of 2011 ETSI has conducted a project to develop a test system prototype for conformance testing of ePassport readers. The objective of this project was to design, build and test a TTCN-3 (Testing and Test Control Notation, Version 3) based test system prototype for ePassport reader conformance testing. This project was a joint effort between the European Joint Research Centre (JRC) in Ispra (Italy) and ETSI in Sophia Antipolis (France). The test language TTCN-3 has already been widely used in many testing projects across different protocols and technologies. However, until this project TTCN-3 has not been applied in the area of contactless smart card testing.

Scope of this project was to build a test system to test an inspection system typically used to read ePassports. To demonstrate the basic functionality and the feasibility, a subset of BSI TR-03105 Part 5.1 was specified and implemented in the test system.

The following image describes the architecture of the ePassport reader test system developed during this project:

Architecture of test system based on TTCN-3 for ePassport readers (Source: ETSI White Paper No.7)

The most significant part in the architecture is “TTCN-3 Test Component”. This module simulates the ePassort behaviour by receiving APDUs, react to these commands and send result in APDUs back to the SUT (here the ePassport reader).

The successful implementation of a TTCN-3 based test system shows that the use of TTCN-3 fits the requirements of conformance testing of eMRTD or other eID systems. The prototype demonstrates the feasibility of using such formal techniques for protocols which would improve the quality and repeatability of tests and reduce room for interpretation.

The MRTD group of ICAO has released an update (version 2.06) with clarifications of their technical report RF and Protocol Testing Part 3 focusing on conformity test and protocol testing for ePassports implementing protocols like BAC and Supplemetal Access Control (SAC) respective PACEv1.

The new version 2.06 of TR-03105 Part 3.2 focusing on protocol testing includes the following changes:

General: Several test cases accept now additionally also an Execution Error in expected results.

General: Instead of ePassports we are talking now about eMRTD.

General: An additional profile was added: “EAC or PACE or AA-ECDSA”.

General: The profiles of several test cases were extended.

General: Compatibility to both PACE and BAC in most test cases of ISO_D and ISO_E.

General: Use CAR from DV certificate during Terminal Authentication instead of reading CAR from file EF.CVCA.

ISO7816_C_04: The command GET CHALLENGE must not have been performed.

ISO7816_P_10: This test case was deleted.

ISO7816_P_73: Allows multiple PACEInfo if just one parameter ID is being used.

ISO7816_P_74: Allows multiple PACEInfo if just one parameter ID is being used.

ISO7816_P_75: Requires two PACEInfo elements using the same OID and different parameter IDs.

LDS_A_03: Now LDS version 1.8 is also accepted.

LDS_B_13: Added new assertions on the date (day and month).

LDS_D_06: Additional test step checking the LDS info object.

In the past I have missed such a list for every new released version of test specifications, like BSI TR-03105 or ICAO technical reports. You can find a list of modifiied test cases for protocol testing in the last version of BSI TR-03105 Part 3.2 in a previous post.

So I hope, this list of modified test cases is helpful for your work in context of ePassport testing. If you are interested, please leave a comment and I will update this list with every new version of test specifications in context of smart cards used in ePassports and ID cards.

The European Commission (EC) and the International Civil Aviation Organization (ICAO) has organized a SAC interoperability test in Madrid end of June 2014. The objective of this interoperability test was to assure that European countries are ready to launch Supplemental Access Control (SAC) respective PACEv2 at the end of this year. The following countries participated in the test (in alphabetical order):

Australia

Austria

Belgium

Bosnia Herzegovina

Czech Republic

Finland

France

Germany

Iceland

Italy

Japan

Netherlands

Norway

Portugal

Slovenia

Spain

Sweden

Switzerland

The SAC interoperability test was also open for industry. The following vendors participated with their ePassport solutions (in alphabetical order):

3M

Arjowiggins

Athena

De La Rue

EDAPS

Gemalto

Giesecke & Devrient

IRIS

Masktech

Oberthur

PWPW

Safran Morpho

Toshiba

Every participant had the chance to submit up to two different sets of ePassport with different implementations. Altogether there were 52 samples available during the test session. All ePassports were tested in two different test procedures: Crossover Test and Conformity Test. Here the Conformity Test is focused on, because protocols are in foreground in this kind of test. There were three test labs (Keolabs, TÜViT + HJP Consulting and UL) taking part in the interoperability test with their test tools to perform a subset of “ICAO TR RF Protocol and Application Test Standard for e-Passports, Part 3”. The subset includes the following test suites:

ISO7816_O: Security conditions for PACE protected eMRTDs

ISO7816_P: Password Authenticated Connection Establishment (PACEv2)

ISO7816_Q: Command READ and SELECT for file EF.CardAccess

LDS_E: Matching between EF.DG14 and EF.CardAccess

LDS_I: Structure of EF.CardAccess

During the conformity test, all three test labs performed 21.282 test cases altogether. Nearly 3% of these test cases failed during the conformity test.

The following diagram shows the results of the conformity test as part of the SAC interoperability test. There were five samples with zero failure, seven samples with 1 failure, twenty-seven samples with 2, 3 or 4 failures, five samples with 5 up to 20 failures and eight samples with more than twenty failures:

The following diagram shows the failures per sample:

All documents supported either Integrated Mapping (IM), Generic Mapping (GM) or both. The following diagram shows the distribution of the mapping protocols:

In mapping protocol there is a possibility to choose either ECDH, DH or both of them. The samples of the SAC interoperability test supported mostly ECDH, as showed in the following diagram:

The observations of the conformity test (part of SAC interoperability test) are:

the document quality varies from “close to release state” to “experimental state”

there are different interpretations of padding in EF.CardAccess and EF.DG14, encoding of TerminalAuthenticationInfo in EF.DG14, the use of DO84 in PACE and the use of parameter ID when proprietary or standardized domain parameters are used

certificates for EAC protocol (e.g. test case 7816_O_41) were missing or not usable

use of different versions of test specification of test labs (Version 2.01 vs. Version 2.06)

Update 1: You can find a discussion concerning the test results on LinkedIn here.

Update 2: You can find the slides of the presentation we hold at the end of the SAC Interoperability Test here.

The German BSI and French AFNOR have released an update with minor clarifications of their technical guideline BSI TR-03105 Part 3.2 focusing on conformity tests for ePassports implementing protocols like PACE and SAC (EACv1).

The new version 1.4.1of TR-03105 Part 3.2 includes changes in the following test cases:

ISO7816_II_2: The missing profile ‘ECDH’ is added to the profile of this test case according to the corresponding test case ISO7816_I_2 in test suite I.

ISO7816_II_3: There is a new test step added (step 3) to perform the additional command GENERAL AUTHENTICATE to perform key agreement correctly.

ISO7816_K_19: There are several meanings how to handle the ‘presence’ of a data group. A simple command SELECT to detect a data group of the chip is insufficient and may cause problems. In this test case the presence of data group EF.DG15 should be used as an indicator to perform Active Authentication. In the new version of this test case the wording is adapted to TR-03110 and is changed from “is present” to “if available”. On this way the discussion is moved from TR-03105 to TR-03110. From my point of view it makes sense to check if the relevant data group is listed in file EF.SOD. The information in EF.COM is note secured by Passive Authentication and may be corrupted. Instead of that, EF.SOD is secure and can be used as an indicator of the existence of a file on the chip.

ISO7816_L_13: In step 9 of this test case the command MUTUAL AUTHENTICATE is performed. In the old version of the specification this command was not complete. The missing Le byte is now added, so the command expects now 40 bytes (or 28 in hex) as response.

ISO7816_L_14: In the previous version of TR-03105 in step 8 of this test case a SELECT MF with parameter P2 = ‘0C’ is performed. ISO7816-4 specifies for bytes b4=1 and b3 =1 that no response data is expected if Le field is absent. This command causes problems on some COS implementations and so the command is replaced by a SELECT with P2 = ’00’ and Le = ’00’.

In the past I have missed such a list for every new released version of test specifications, like BSI TR-03105 or ICAO technical reports. So I hope, this list of modified test cases is helpful for your work in context of ePassport testing. If you are interested, please leave a comment and I will update this list with every new version of test specifications in context of smart cards used in ePassports and ID cards.

During the ICAO Regional Seminar on Machine Readable Travel Documents (MRTD) in Madrid from 25th to 27th of June 2014 there will be also the opportunity of an interoperability test for ePassports with Supplemental Access Control (SAC). The protocol SAC is replacing Basic Access Control (BAC) used in ePassports and will be obligatory in EU from December 2014. SAC is a mechanism specified to ensure only authorized parties can wirelessly read information from the RFID chip of an ePassport. SAC is also known as PACE v2 (Password Authenticated Connection Establishment). PACE v1 is used as a basic protocol in the German ID card and was developed and specified by the German BSI.

An interoperability test is similar to a plugtest performed e.g. by ETSI. It’s an event during which devices (ePassport, inspection systems and test tools) are tested for interoperability with emerging standards by physically connecting them. This procedure allows all vendors to test their devices against other devices. Additionally, there is the opportunity besides this crossover tests to test the devices against conformity test suites implemented in test tools like GlobalTester. This procedure reduces efforts and allows comprehensive failure analyses of the devices like ePassports or inspection systems. There are well established test specifications available, both for ePassports and for inspection systems. Publishers of these test specifications are the German BSI (TR-03105) or ICAO (TR – RF and Protocol Testing Part 3).

You can find further information corresponding to this event on the ICAO website. The website will be updated frequently.

Back in office after three weeks holiday I would like to show you now one of the high level results doing all these interoperability tests in the domain of ePassports. Today a German consortium (i.a. Bundesdruckerei and Secunet) won a tender for biometric-based eGates rolled out across the country in the next years at several airports. These eGates use well-known protocols as Basic Access Control (BAC) or Supplemental Access Control (SAC) to establish a secure channel between reader and smart card of ePassport via ISO 14443 interface for contactless smart cards. An automatic border control (ABC) like this allows passengers in less than 30 seconds to pass the gate. Currently you can find an alternative of such systems at the airport in Heathrow.

The following figure shows a typical simplified workflow of such a border control system:

To reduce waiting time for passengers the system is using an automatic process. At the beginning the citizen is passing the gate by showing his ePassport. An inspection system scans the machine readable zone of the data page to derivate a cryptographic key to get access to the contactless smart card. As soon as all data groups of chip are read, the inspection system verifies the authenticity of the data to assure validity of the current ePassport chip. In the meantime the face recognition system scans the citizen to get a facial image of him. This image is being compared with the facial image of the chip (biometric verification). If both images are similar and the ePassport is not blacklisted, the citizen can pass the gate.

The results of the InterOp test 2013 concerning the new protocol SAC (Supplemental Access Control) are available. The test event was split into two slots – a conformity test (to test if the document conform to the latest ICAO standards) and a crossover test (to test, if each document can be read by the inspection system). A concluding test report is available here. Thanks to Mark Lockie and Michael Schlüter for organizing this successful event.

Next week another ePassport interoperability test takes place in London. The community will join to test their next generation smart cards in ePassports with the new protocol Supplemental Access Control (SAC) as a replacement of Basic Access Control (BAC). BAC was designed in the beginning of this century and will be replaced by SAC in December 2014 latest. The protocol SAC bases on the well known protocol Password Authenticated Connection Establishment (PACE) that was mainly developed by German BSI and that is also used in German ID cards issued since November 2010. PACE is specified in TR-03110.

During the interoperability test vendors of chips and inspections system will test their implementations against current conformity test suites of several test labs. More information can be found here: InterOp 2013.